Cytomegalovirus (CMV), also known as human herpesvirus 5 (HHV-5), is a herpes virus classified as being a member of the beta subfamily of herpesviridae. According to the Centers for Disease Control and Prevention, CMV infection is found fairly ubiquitously in the human population, with an estimated 40-80% of the United States adult population having been infected. The virus is spread primarily through bodily fluids and is frequently passed from pregnant mothers to the fetus or newborn. In most individuals, CMV infection is latent, although virus activation can result in high fever, chills, fatigue, headaches, nausea, and splenomegaly.
Although most human CMV infections are asymptomatic, CMV infections in immunocompromised individuals, (such as HIV-positive patients, allogeneic transplant patients and cancer patients) or persons whose immune system has yet fully developed (such as newborns) can be particularly problematic (Mocarski et al., Cytomegalovirus, in Field Virology, 2701-2772, Editor: Knipes and Howley, 2007). CMV infection in such individuals can cause severe morbidity, including pneumonia, hepatitis, encephalitis, colitis, uveitis, retinitis, blindness, and neuropathy, among other deleterious conditions. In addition, CMV infection during pregnancy is a leading cause of birth defects (Adler, 2008 J. Clin Virol, 41:231; Arvin et al, 2004 Clin Infect Dis, 39:233; Revello et al, 2008 J Med Virol, 80:1415).